FUTABA GY520 User manual

1M23N21902
INSTRUCTION MANUAL
YAW-AXIS STABILIZER FOR MODEL HELICOPTER
(RATE GYRO)
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TABLE OF CONTENTS
Technical updates and additional programming
examples can be found at:
www.futaba-rc.com/faq
• Precautions----------------------------------------------------- 3
• Warranty and Repair Service (in U.S.A.) ------------------ 6
• Contents -------------------------------------------------------- 7
• Specifications -------------------------------------------------- 8
• Recommended Servos---------------------------------------- 9
• Replacement and Optional Items --------------------------- 9
• Function and Connection Diagram ----------------------- 10
• LED Indicator Description----------------------------------11
• Introduction ---------------------------------------------------11
• Mechanics Preparation ------------------------------------- 12
• GY520 Installation------------------------------------------ 13
• Connecting the GY520 to your Receiver ---------------- 15
• GY520 Programming--------------------------------------- 16
• Tail Rotor Servo Installation and Setup ------------------ 25
• Before Flight Checklist------------------------------------- 28
• Adjustments During the Test Flight ---------------------- 29
• Using Normal Mode ---------------------------------------- 30
• Setting the Gain --------------------------------------------- 31
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PRECAUTIONS
WARNING!
Failure to follow these safety precautions may result in
severe injury to yourself and others.
• Read through the entire manual before operating this product.
• The GY520 requires 5-10 seconds to initialize when the
power is turned on. Do not move the helicopter and do
not move the tail rotor stick during this initialization
or the gyro may not initialize properly. Once the
initialization process is complete, the tail rotor servo will
move to the left extent and then to the right extent. This
will occur twice. The indicator light will change to solid
blue for AVCS Mode or solid red for Normal Mode.
BEFORE EACH FLIGHT:
• Always check the transmitter and receiver battery voltage to
ensure they have enough remaining capacity to complete
the flight.
• Verify that the gyro is operating correctly.
• Verify that the gyro compensates in the correct direction
before flight. If the compensation direction is incorrect the
model will pirouette uncontrollably, at a very high rate.
• Verify that the gyro is operating in the desired mode.
• Verify that the gyro mounting pads are in good condition.
• Verify that the gyro wires are not contacting the frame of
the helicopter.
• The servo type parameter within the GY520 must match the
type of servo you are using. Incorrect setting may damage
the GY520 or the servo, possibly resulting in a loss of control
during flight.
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PRECAUTIONS
• Only use the GY520 with a 2.4GHz system such as the
Futaba FASST™system, or a PCM system. Use with a FM
system is strongly discouraged since interference can
cause serious operational problems. In addition to this
the latest high performance tail rotor servos generate
electrical noise which may also cause interference to an
FM receiver.
• Always ensure that there is some slack in the gyro cables
to help maximize performance. Always use the supplied
gyro mounting pads to attach the gyro to the helicopter
mechanics. Do not use a strap that encompasses the GY520.
This may affect the overall performance of the gyro.
• Always allow the gyro to adjust to the surrounding
environmental temperature before flight. A large temperature
change during use will cause drift and other operational issues.
• The GY520 uses a conductive resin case to prevent
electromagnetic interference. Do not allow anything to touch
the gyro case as it may cause a short circuit.
• If you are switching between Normal Mode and AVCS Mode
in flight, please keep in mind that you must have the gyro
re-learn the center position after making a trim change within
the transmitter. To memorize the new center position simply
flip the gain switch on the transmitter three times between
Normal Mode and AVCS Mode within one second. The tail
rotor servo will center indicating that the new center position
has been memorized.
• When the GY520 is used in Normal Mode, tail rotor
compensation or revolution mixing must be used within
the transmitter.
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PRECAUTIONS
• When operating the gyro in AVCS Mode, all tail rotor
compensation and revolution mixing must be disabled and
any tail rotor offsets for flight modes must be disabled.
• When the GY520 is operated in AVCS mode the tail rotor
servo will not center when the stick is released. This is
normal operation for AVCS mode. The servo may also move
to the extent while the model is being carried out to the flight
line. Before take off, you must center the tail rotor servo by
moving the tail rotor stick full left, then full right, back to full
left and then allow the stick to center within one second. You
can also visually center the tail rotor pitch slider by using the
tail rotor stick.
• Do not drop the GY520 onto a hard surface or subject the
GY520 to a strong shock as this may damage the sensor.
Always use the supplied mounting pads or the Futaba
replacement mounting pads available from your local
hobby dealer.
• Always exit programming mode before attempting to fly
the model.
• Do not use any type of priority mixing or gain reduction
mixing on the GY520.
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WARRANTY & REPAIR SERVICE (IN U.S.A.)
If any difficulties are encountered while setting up or operating
your GY520, please consult the instruction manual first. For
further assistance you may also refer to your hobby dealer,
or contact the Futaba Service Center at the web site, fax or
telephone number listed below:
www.futaba-rc.com or www.hobbyservices.com
Fax [phone], Tel [phone]
If you are unable to resolve the issue, pack the system in its
original container with a note enclosed and a thorough, accurate
description of the difficulty. Include the following in your note:
• Symptoms (including when the problem occurred)
• System (Transmitter, Receiver, Servos and model numbers)
• Model (Model name)
• Model numbers and quantity
• Your Name, Address and Telephone number
Send the respective items to the authorized Futaba Service
Center Address below:
Futaba Service Center
3002 N Apollo Drive Suite 1
Champaign, IL 61822
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CONTENTS
Mounting Pads
2mm Thick (two)
3mm Thick (two)
Adjustment Screwdriver
GY520 Gyro
G
Y520
Gy
r
o
Damping and
Shield Plate
Extensions
Tail Rotor Extension (Black)
Gain Extension (Red)
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SPECIFICATIONS
Width: 0.79in [20mm]
Length: 0.79in [20mm]
Height: 0.39in [10mm]
Weight: 0.243oz [6.9g]
Maximum* Operating Voltage: 3.8V to 6.0V DC (Gyro only)
Current Drain: 40mA (Gyro only)
Selectable Servo Frame Rate: 70Hz, 280Hz and 560Hz
Center Pulse Width: 1520 S (70Hz & 280Hz Frame Rate)
760 S (560Hz Frame Rate)
Flight Mode: User selectable F3C or 3D
Operating Temperature: 14ºF to 113ºF
Control System: Advanced PID control
Sensor: MEMS vibrating structure gyro
Angular Velocity Range: ±800 Degrees Per Second
*The maximum operating voltage listed only applies to the GY520.
Always verify that your receiver, servos, tail rotor servo, governor, switch
and any other electronic components used in your installation are capable
of operating at the voltage you plan to use.
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250 – 450 Sized Electric
Futaba S9257 EP Heli Digital (280Hz/1520μS): FUTM0667
.30 – .91 Size Helicopters
Futaba S9254 Digital Servo Heli (280Hz/1520μS): FUTM0224
Futaba S9256 Digital Hi Speed (560Hz/760μS): FUTM0226
Futaba BLS251 Brushless Heli Servo (560Hz/760μS): FUTM0521
Futaba PC Interface CIU-2 for GY520: FUTM0951
FSH64 GY520 Extension 200 mm (2): FUTM4664
FSH65 GY520 Extension 350 mm (2): FUTM4665
FSH66 GY520 Extension 55 mm (2): FUTM4666
FSH67 GY520 Extension 80 mm (2): FUTM4667
FSH68 GY520 Extension 130 mm (2): FUTM4668
FSH69GY520 Mounting Pad 2x22x22 mm (10): FUTM4669
FSH70 GY520 Mounting Pad 3x22x22 mm (10): FUTM4670
FSH71 GY520 Shield Plate 1x22x22 mm (3): FUTM4671
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RECOMMENDED SERVOS
REPLACEMENT & OPTIONAL ITEMS
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FUNCTIONS & CONNECTIONS
Button
LED Indicator
Gain
Channel
Tail Rotor
Channel
Tail Rotor Servo
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LED INDICATOR DESCRIPTION
Initialization Slow Red Flash No Receiver Pulse or Sensor Error
Slow Blue Flash Warm-Up
Fast Blue Flash Sensor Initialization
Operating Solid Blue Normal Mode, Ready for Flight
Solid Red AVCS Mode, Ready for Flight
Slow Violet Flash Offset from the Neutral Position
Fast Blue or Red Flash Gyro is Rotating
CONDITION LED INDICATOR DESCRIPTION
Slow Flash: 1/2 Second or longer
Fast Flash: 1/4 Second or shorter
INTRODUCTION
The Futaba®GY520 is the smallest and lightest heading hold
AVCS gyro available today. Its cutting-edge MEMS (Micro Electro
Mechanical System) sensor design, ultra high-speed processing
speed and advanced PID control algorithm put it a quantum
leap ahead of all other heading hold gyros in size, weight and
performance. The GY520 has been optimized to work with small
electric models and larger nitro (.30 through .91) sized helicopters.
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MECHANICS PREPARATIONS
WARNING!
• Newer high end servos and other radio equipment are
capable of placing large demands on the power systems
in use today. When using a regulator you must ensure
that the regulator is capable of delivering the current
demands of the equipment you have selected. In addition
to this make sure the wiring and switch you have
selected are capable of handling high current draws.
• Even though the GY520 is a high performance gyro it will be
necessary to ensure that the helicopter mechanics are also
in optimum operating condition. Please use the guidelines
below and address all issues before installing and test flying
the GY520.
• The GY520 must be used with a rigid tail rotor drive system.
Any modern torque tube or belt drive system should be
adequate. Do not attempt to fly the GY520 using a wire
driven tail rotor system.
• Always ensure the drive gears, torque tube, pulleys, belt,
bearings and shafts are in proper working condition. If any of
these items are damaged or worn they must be replaced.
• The linkage rod, tail rotor bell crank, pitch slider and tail
rotor grips must operate without friction to obtain the best
performance from the GY520. If any binding is present it
must be fixed before the helicopter can be flown. Binding in
the tail rotor control linkage will decrease the performance of
the GY520 gyro and this may also shorten the servo lifespan.
Please take the time now to ensure the tail rotor system on
your helicopter is working correctly, without friction or binding.
• Vibration will affect the gyro’s overall performance. All
rotating components on the helicopter should be balanced
to minimize vibrations in flight. Ensure that your motor is
running smooth and all vibrations have been addressed
before installing and test flying the GY520.
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GY520 INSTALLATION
The gyro should be mounted on a rigid platform, at least
6in [152mm] away from a Nitro Engine. It is not necessary
to mount the gyro near the main shaft of the helicopter but
it is very important that the mounting area chosen is rigid.
Please refer to your helicopter manufacturer’s instructions for
recommended mounting locations.
Installing the gyro
The GY520 is supplied with two 2mm Mounting Pads, two
3mm Mounting Pads, and one 1mm Damping and Shield
Plate to help accommodate several installation methods. Most
electric helicopters with minimal vibrations can use one 2mm
mounting pad to mount the gyro onto the Gyro Mount. If the
GY520 is mounted near the ESC, near a servo, or near the tail
rotor belt we highly recommend using two 2mm Mounting
Pads and the steel Damping/Shield Plate to help prevent
electromagnetic interference from reaching the gyro.
2mm Mounting Pad
Gyro Mount
Recommended Installation for Smaller Electric Helicopters
(250, 450, and 500 size helis)
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GY520 INSTALLATION
2mm or 3mm
Mounting Pads
Gyro Mount
Damping and
Shield Plate
Recommended Installation for Larger Electric Helicopters
and All Nitro Helicopters
On smaller electric helicopters it is best to mount the gyro using
one 2mm mounting pad. When mounting the gyro in a larger
electric or .50 through .91 size nitro helicopter we recommend
using two 3mm Mounting Pads and the Damping/Shield Plate.
TROUBLESHOOTING
If you experience erratic gyro operation (drifting, not holding
well or inconsistent pirouette rate), please follow the
troubleshooting tips listed below.
1. Always verify that your model’s tail rotor control and drive
system are working correctly.
2. Electromagnetic interference could affect the gyro or
tail rotor servo. Use the metal damping and shield plate
or mount the gyro in a different location, away from the
electronic speed control, servos and drive motor.
3. The trouble may be caused by vibration. Verify that your
helicopter’s components are balanced. If problems persist,
try mounting the gyro in a different location. Various
combinations of the gyro mounting tape may help to mask
the issue.
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CONNECTING THE GY520 TO YOUR RECEIVER
Red: Gain
Channel
Tail Rotor
Servo
Black:
Tail Rotor
Channel
Connect the supplied extensions to the GY520 connecter block as
indicated. Route the wires through the helicopter mechanics and
connect them to the appropriate receiver channels. To determine
the appropriate receiver channels please check your transmitter’s
instruction manual. Using a piece of double sided tape, mount
the GY520 connector block onto the helicopter, ensuring that
you leave some slack in the wire leading to the gyro. Using wire
mounts, wiring fixtures molded into the helicopter, or hook and
loop material, route the extensions to the receiver. Ensure that the
extensions leading to the receiver cannot become entangled in
rotating components and make sure the extensions are not rubbing
against metal or carbon fiber which may damage the wires.
Once the power system is installed into your helicopter please
move onto the next section to learn how to program the gyro.
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GY520 PROGRAMMING
Entering Programming Mode
Press and hold the button on the side of the GY520. After
3 seconds the LED indicator will momentarily change to violet.
Release the button and the gyro will begin flashing once per
second. The color shown is the option selected for the 1st
parameter [Servo Type]. For example, if you see one Blue Flash
then the [Servo Type] is set to Digital 1520 S. If you see one
Red Flash then the [Servo Type] is set to Digital 760 S servo.
The number of flashes is the parameter number you are viewing
and the color of the LED indicates the setting that has been
selected. Please see the GY520 Parameters and Settings Table.
Changing the setting within a parameter
To move to the next setting within a parameter, quickly (less
than one second) press and release the button on the gyro. The
LED will begin flashing rapidly. This indicates that the gyro
needs confirmation of the change. While the LED is flashing,
rapidly press and release the button again to confirm the
change. The confirmation request flash will last one second,
after this period of time the gyro will return to the parameter
menu without making a change. Always ensure that the change
has taken place by counting the number of flashes and verify
the color of the indicator LED.
Moving to the next Parameter
Press and continue to hold the button on the side of the GY520.
After 2 seconds the LED indicator will momentarily change to
violet. Release the button and the gyro will move to the next
parameter. The number of flashes will change to reflect this.
Button
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GY520 PROGRAMMING
* Default Setting
1. Servo Selection
3. Servo Limits
6. Data Reset
4. Flight Mode
5. Response
2. Gyro Compensation
Direction
Digital 1520μS Servo* Blue, 1 Flash
Digital 760μS Servo Red, 1 Flash
Analog Servo Violet, 1 Flash
Normal* Blue, 2 Flashes
Reverse Red, 2 Flashes
Blue, 4 Flashes
3D Mode Red, 4 Flashes
Standard* Blue, 5 Flashes
Fast Red, 5 Flashes
Slow Violet, 5 Flashes
(Resets Settings 1 – 5) Blue, 6 Flashes
Red, 3 Flashes
F3C Mode*
PARAMETER SETTING LED INDICATION
S
D
F
S
D
1
.
S
3. S
6
.
D
4
.
F
5
.
R
2
.
G
D
3S
D
4
F
3.
S
6D
G
2G
GY520 Parameters and Settings Table
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Select the appropriate setting for the servo you are using.
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GY520 PROGRAMMING
Parameter 1: Servo Type [1 FLASH]
WARNING!
The servo type parameter within the GY520 must match the
type of servo you are using. Incorrect setting may damage the
GY520 or the servo, possibly resulting in a loss of control of
the model during flight.
Blue, 1 Flash
Digital 1520μS Servo*
Red, 1 Flash
Digital 760μS Servo
Violet, 1 Flash
Futaba S9650 EP Heli Digital Servo
Futaba S9257 EP Heli Digital Servo
Futaba S9253 Digital Servo
Futaba S9254 Digital Servo
Any digital servo capable of a 280 Hz update rate.
Futaba S9256 Digital High Speed Servo
Futaba BLS251 Brushless Heli Servo
All analog (non-digital) servos.
Futaba S9251 Digital High Speed Servo
LED INDICATOR
SERVO TYPE SERVO COMPATIBILITY
* Default Setting
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GY520 PROGRAMMING
Parameter 2: Gyro Compensation Direction [2 FLASHES]
This parameter controls which direction the gyro will compensate
when the helicopter rotates. Once the tail rotor linkage is connected
to the servo, pick the helicopter up by the main shaft and rotate
the mechanics counter-clockwise. The gyro should compensate
by adding clockwise rotation pitch to the tail rotor blades. If the
gyro compensates by adding counter-clockwise rotation pitch to
the tail rotor blades then it will be necessary to reverse the Gyro
Compensation Direction setting.
WARNING!
Verify that the gyro compensates the correct direction before
flight. If the compensation direction is incorrect the model will
pirouette uncontrollably at a very high rate.
Red, 2 Flashes
Blue, 2 Flashes
Normal Compensation*
Reverse Compensation
LED INDICATOR DESCRIPTION
* Default Setting
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GY520 PROGRAMMING
Parameter 3: Servo Limits [3 FLASHES]
Red, 3 Flashes
Blue, 3 Flashes
Limit Testing Mode
Set limit using tail rotor stick.
LED INDICATOR DESCRIPTION
The Servo Limit parameter is used to set the mechanical limits for the
tail rotor servo. To obtain the highest performance it is recommended
to adjust the servo arm length to set the mechanical limits and then
use the servo limits parameter to make small adjustments.
WARNING!
• To prevent damage to the servo always perform limit setup
with the tail rotor linkage disconnected and simply hold the
linkage over the linkage ball to verify settings.
• While in the servo limits parameter the gyro no longer
functions. Always ensure that the gyro is functioning correctly
and it is not in the servo limits parameter before flying
the helicopter.
Setting the servo limits:
Go to the SERVO LIMITS parameter. While in the servo limits
parameter the gyro compensation no longer functions and the tail
rotor servo will always center. This can be used to set the centering
position for the tail rotor linkage and the tail rotor stick can be
moved to verify that the limits are set correctly. While in the servo
limits parameter the tail rotor stick is 150% more effective to
compensate for any tail rotor AFR or D/R adjustments made within
the radio. Please do not be concerned if the tail rotor servo reaches
its limit before the tail rotor stick reaches its physical limit.
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